ST. LOUIS (KSDK) - The Gateway Arch has been included on the World Monuments Fund's 2014 watch list for at-risk monuments.

"...the Arch stands as a symbol of westward expansion in the United States and as an icon of mid-century modernism," the WMF website reads. "But as is the case with many important examples of modern architecture, the preservation of twentieth century materials and structural designs has proven challenging.

"The unusual shape and extreme height of the Arch compound these difficulties, as do economic trends that have led to decreased government funding for the stewardship of national memorials."